In the medical field, injection sites usable with pointed cannulae have long been known. For example, such sites can be formed with a housing having a fluid flow path therein. A septum is positioned in the housing closing the fluid flow path.
A pointed cannula can be forced through the septum into fluid flow communication with the flow path in the site housing. Known injection sites usable with a piercing cannula can be physically damaged by repetitive piercing caused by the sharp cannula. This damage, known as coring or laceration, can result in subsequent leakage.
Further, a large number of drugs are packaged in well known glass or plastic drug bottles or vials having rubber-like stoppers. Similar to injection sites, the stoppers on the drug vials are pierceable by a needle or cannula having a sharpened tip when secured to a syringe assembly of a well-known construction. Typically, the needle is brought to a point on one side of the needle wall by a bevel structure so that the needle tip is quite sharp. Drug vials are also subject to coring by such needles. Particulate matter can subsequently be generated and injected into the patient or otherwise contaminate the content of the vial.
Due to problems associated with infectious agents, personnel using such pointed cannulae or needles do so with great care. Notwithstanding careful and prudent practice, from time to time, accidents do occur and individuals using such pointed cannulae accidentally "stick" themselves.
In an effort to overcome some of these difficulties, devices known as "dispensing pins" can be used to penetrate the stopper of drug vials. Such dispensing pins are typically a sharp spike cannula and can employ a check valve in an effort to prevent gross fluid leakage. On the opposing end of the cannula is a standard luer fitment typically closed off, when not in use, by a cap. These dispensing pins tend to disengage from the vial stopper so that some leakage may occur.
Disclosed in pending U.S. Application Ser. No. 07/425,790, filed Oct. 23, 1989, a pre-slit injection site coupled with a component to adapt the site to standard drug vials has been developed to address these same difficulties. Primarily developed for use with multi-dose vials, such an adapter can be lockingly engaged with a drug vial, thereby permitting the usage of a blunt cannula rather than a sharp cannula or needle. However, this adapter may not be a cost efficient device when used with single-dose drug vials.